Last night's 2-2 draw with KuPS means Palace must now play a two-legged play-off in February against either HŠK Zrinjski Mostar from Bosnia and Herzegovina, or SK Sigma Olomouc from Czech Republic.
The result left Palace in tenth place on the Conference League table and so placing them in the playoffs group.
Glasner lamented afterwards: “The result is not what we wanted and I think this was a game we could have easily won.
“For 10 minutes, we lost our structure and then we were punished with two mistakes. But this can happen, especially with many young players, but I think we played a very good first-half.
“Lots of credit to every single player, especially to our Academy players. I think they showed very good performances. We could see that they are not used to playing at this level because all four were cramping, starting after 60 minutes, but I think they showed very good performances."
Poor finishing
Glasner also admitted: “It looks like in the Conference League it's very often the same story, like with the Larnaca game at home: creating chances and missing and missing, not deciding the game, and then making one mistake. Jaydee (Canvot) made one against AEK Larnaca, we got punished. Today we made two and we got punished, so three finishes (for KuPS), scoring two goals.
“That's a little bit the story, especially for our Conference League games. Let's take the tough pathway: after demotion, playing two qualification rounds in August, now we'll play two more games in February, so the fans can travel to another country.
“It's February. There will be a few players back. Today, we had a few players who said, ‘Gaffer, we have three games in five days, I can play every game for 90 minutes.’ I said, ‘calm down’. It just shows the character of this team.
“Yes, we would have preferred to win, but everything else, we calculated this risk of maybe getting a draw, but everything else worked how we planned it. We could rest a few players.
“The only thing that I don't like is Leeds now knows our starting line-up already, because we have just 11 players who did not start – so when I mentioned nobody will start in both games, that's the only thing I don't like tonight, but (Leeds manager) Daniel Farke will know it now!”